Multispeed drive axle



MULTISPEED DRIVE AXLE Filed Oct. 3, 1941 Lawrence 2?. Baa/{enable I *Wnm/ Patented Aug. '17, 1943 pair s stares r pri'r'rsrnnn'nar n AXLE Lawrence R. Buckendale, Detroit, Mich; assignor to The Timken-Detroitz lxie Company, Detroit,

Mich a corporation of Ghio Application Qctober 3, 1941, Serial No. 413,539-

3 Claims.

The present invention relates to multi-speed power transmitting mechanisms and more particularly to'planetary drive axles, although it is notlimited to such use. v

Although planetary drive axles have been in use for a number of years in the truck and bus field, and recently have gone into limited use in,

pleasure cars to provide an overdrive at the higher or cruising speeds, they do not fully satisfy the requirements of moderntransportation, primarily because they lack a sufiiclent degree of speed reduction, nor do they provide a suliicient number of speeds to" aiford the proper degree of flexibility to meet all o-perating'condi- ,tions encountered in normal service."

In my co-pending application Serial No. 413,538, filed on even date herewith, for Multispeed drive axle, there is disclosed a drive axle embodying a combination of planetary and non-' lanetary units, which provides a greater degree of speed reduction than the axles nowv in use, and the present invention deals with a drive axle having all of the. advantagesof that construction and in addition provides additional selectively available speed ratio and further novel improvements and refinements.

The major object of this invention is to provide a novel drive axle having planetary and non-planetary two-speed gear mechanisms arranged in series and operable to transmit power from the drive shaft'to the axle shafts, which is low in cost, simple in design, and yet efficient and durable in service.

Another important object is to provide a drive axle having parallel counter and axle shafts, with two-speed spur and planetary mechanisms associated respectively with the counter and axle shafts and operable to transmit power therebetween at a plurality of different speed ratios.

A further object is to provide a drive axle with a novel planetary mechanism having a rotor made up of a plurality of detachable sections in the drawing, the single figure is a horizontal longitudinal section through. a drive axle embodyinglthe'invention, part of t the housing Joeing shown in top planview to simplify the disclosure. Very briefly, the mechanism comprises a, pinion shaft transmitting po-werthrough 'ajbeveli gear set A to a countershaft from which power is transmitted through a spur gear setJB to 'a planetary rotor C. Power is'selectively transmitted from the latter to the axle shafts at two diiierent gear ratios by means of a'planetar'y mechanism designated as D. s

The mechanism is contained in a divided housing made up of a main section In and'an auxliary housing'se'ctionll. The two sections are clamped together along a plane 7 transverse to the axle shafts'in well known manner (not shown); A pair of axle shafts-1'2 and i3 are journalled in axle arms carried by the housing sections inwell -known rnann'er, and are splined to differential side gears l4 and I5,

respectively.- Miter gears 16, carried by a differential' spider IL mesh with the differential side gears and divide the power between' the two axleshafts inwellgknown manner.

PRIMARY Darya- V 'Power is transmitted to the axle by "means of a pinion shaft l8 journalle'd'ina front bearing (not shown) and a rear bearing l9 lo'ated'ifn a bearing sleeve 2| secured to housing section In in well known manner. A sleeve, 22 cooperates with the inner bearing races to provide the proper working clearances in well known m-ann er.

Pinion shaft LE3 is accordingly mounted for rotation in the housing and may be removed as a unit, along with its bearings, by removing sleeve 2|. Shaft l carries a, bevel pinion 23 which mesheswith a bevel gear .24 rigidly secured to'a countershaft 2-5. If" desired, the gears may be of either the spiral bevel or the hypoid type. Also, if desired; worm'or other'well known types of gearing may be used in place of the bevel gears shown. r

By providing anop'ening 26 in housing section ill of sufficiently large diameter to receive gear 2 3, and supporting the shaft in a closure assembly detachably secured. over the opening, the entire countershaft assembly may be readily rernovedby removing the closureassembly, and sliding the assembly as a unit .to the right'and out of the housing.- y

In the present instance the closure assembly has been shown ascompris'ing an internally ribbeclmember 21, having a, piloting 'sur facelfi i F F E transversely snugly engaging opening 25. The closure assembly is detachably held in place by means of cap screws (not shown), and preferably a pinrality of shims 29 are interposed between it and the face of the housing to provide the proper bearing adjustment. Mounted in an annular seat 3! in closure 21 is the outer race of an antifriction bearing 32. The inner bearing race is secured to a reduced portion 33 of a countershaft by means of a nut 34 anda lock ring 35.

The other end of the countershaft is journalled in a bearing 31, whose outer race is carried in a seat 38 provided in housing section It.

shaft ata speed reduction, and that a further speed reduction is effected through the low and high speed spur gear mechanism. The particular including cover 2?, may be removed from the The inner bearing race is held on a shaft by a.

possible to avoid splitting the housing adjacent the plane of the propeller shaft, and to provide both of the countershaft supports in a single housing;

SPUR GEAR REDUCTION Power is selectively transmitted from the countershaft to the planetary'rotor' at two different speed ratios by means of a spur gear mechanism that will now, be described, and which doubles the number of speed ratios available in the planetary unit.

Mounted for free rotation on the countershaft are low and high speed pinions 42 and 43 provided with clutch teeth 44 and 45, respectively, which cooperate with a toothed clutch member 46 coacting with teeth 4'! provided on the countershaft. The clutch member is provided with a yoke groove 48 in which the arms of a shifter The shifter yoke is mounted upon a shaft 49, and secured to the shaft, externally of the housing, is an actuating lever 51 having a finger portion 52 cooperating with stop pins 53 and 54 on the housing. The high and low speed pinionsmesh with spur gears 55'and 56, respectively, carried byjplanetary housing structure C.

Operation With clutch 46 in the position shown in the drawing, and with the countershaft being driven by the bevel gears, countershaft teeth 4'1 drive clutch member 46, which in turn through'teeth 44 drive low speed pinion 412} The low speed pinion is accordingly synchronously driven with the countershaft, and drives gear 55 and the planetary. rotor in the low speed ratio.

When clutch member 461is shifted into its right hand position, it meshes with teeth 45 and causes high speed pinion 43. to rotate synchronously with the countershaft and drive gear 55 and the rotor in the high'speed ratio.' When the clutch. member is disposed in its mid position, no power is'transmitted and the unit is in neutral. 5

The spur gear assembly just described is more fully disclosed in the co-pending application of Nelson R. Brownyer for Power transmission mechanism filed April 10, 1941, Serial No. 387,977, which may be referred to for a more complete disclosure thereof.

From the foregoing disclosure it is apparent that power is transmitted through the constantly meshed bevel gear set to the counterit being understood that the gear sizes will be so'chosen as to afiord the proper gear reduction necessary to suit the requirements of the particular installation involved. It is also to be understood that if a further gear reduction between the propeller shaft l3 and countershaft is desired, the entire countershaft assembly,

1 mechanism and be replaced bya combined planetary gear mechanism and countershaft assembly of the character shown in my co-pending application filed Oct. 3, 1941, for Multispeed drive axle, Serial No. 413,540.

PLANETARY MncHAmsm Power is transmitted from rotor C to the axle shafts at two different speed ratios by means of a planetary gear mechanism which is compactly associated with the axle shaft and spur gear asclamped between'mating faces provided on sections 58 and 5t by means of "stud and nut assemblies 62. Pilot faces 63 are provided on the rotor sections and cooperate with the web of the gear to insure accurate alignment of the sections.

Gear 55 is clamped between rotor sections 59 V and Si by means of stud and nut assemblies 64,

yoke (not shown) ride in well .known manner. 7

and similar piloting faces 65 on the rotor sections cooperate with the internal surface of the gear. The resulting construction is extremely rigid andyet is of light weight and may be readily'disassembled' for service and replacement of parts. 7 p

- The end sections of the rotor are provided with hub portions 5'! and 68, which are journalled in bearings 69 and 1!, respectively. Bearing 69 is carried in a ring-like support 12 having a bearing supporting flange l3 and a set of internal teeth M. The support is secured to an inwardly directed flange in the housing by means of stud and nut assemblies 15. Bearing TI is carried in a seat is formed directly in housing section I0.

The rotor structure is accordingly mounted for accurate rotation in the housing sections about the axis of the axle shafts, and by clamping the spur gears betweenthe rotor sections, they mutually reinforce each other and also simplify assembly and disassembly of the structure. Also, by removing housing section I I, and shifting the rotor bodily to the left, sufiiciently to remove bearing H from its outer race,'the rotor may be completely removed. from the mechanism. After removal of the rotor, closure assembly 21 may be removed and the countershaft assembly slid to theright and removed from the casing. If desired, sleeve 2| may be unbolted and slid forwardly out of the housing to complete the disassembly operation.

Power is' transmitted directly from rotor section 553 to a plurality of shafts 13, which are rigidly secured in aligned openings in section 58 and in a ring member 153. The ring and rotor section 58 are each provided, intermediate shafts 78, with matching bosses and are rigidly bolted together (not shown) in well known manner.

Ring 19 is provided with a "hub portion f in which side gear M, isfjournalledbside gear f5.

being journalled in" a "bore SZprovidedin' rotor section 59. i 3 I Aplanet gear. 83 is journalledjoneach shaft [3 and constantly meshes with 'an orbit ortr'ing gear 85 secured to a differential casing 85 by 7 means of bolt and nut" assemblies 85. Casin in place between the halves in'WeH known man'- ner. Casing'85is provided with spaced Web portions 88 and 89 having thrust washers on their opposite faces, Which'limit'axial' movement of the casing by engaging rin 19 at one end and the honor rotor sectionfisat'the' other. Webs B8 and 89 are spaced from thehubs of gears I4 and I5, with the result that casing 85, through internal gear 84 and miter gears 16 floats respectively on the pitch lines of planet gears 83 and side gears i6 and H.

Planet gears 83 also constantly mesh with sun gear teeth 9| provided on a sleev or'aquill member 92, which is mounted for both rotational and axial movement in thehousing. Sun gear teeth' SI are also adapted to mesh with internal teeth Q3 provided inside rotor section 58. The quill is also provided with external teeth 9 adapted to be selectively meshed with stationary teeth 14/ i 1 i The quill is adapted to be shifted into its various operative positions by means of a yoke member 96, having pins 517 riding in a groove 98 in the quill. The yoke is rigidly secured to a shaft 99, and secured to the shaft externally of the housing is an actuating lever l8 5.

Access to the yoke mechanism is obtained through an opening 102 in housing section H, and adapted to be closed by a plate m3 detachably secured in place.

Operation I ternal gear 8 3 to be revolved in the same direction, but at a higher speed than shaft iii. Casing 85 is therefore driven at an increased speed or at an overdrive ratio.

When lever iEil is operated to shift the quill to' the left, sufficiently to disengage teeth 9 from teeth M, but insufficiently to bring the sun gear into mesh with teeth 93,110 power will be transmitted through the mechanism because rotation of planet shafts i8 merely causes the planets and quill to idle without transmitting power to casing 85.

Assuming now that the quill is shifted into it extreme left-hand position, with sun gear teeth 9| in mesh with teeth 93 of rotor section 53, and also in partial mesh with the planets, the latter are locked against rotation about their axes, with the result that rotation of the planet shafts about the rotor axis causes the locked planets 83 to drive ring gear 85 and casing 85 synchronously with rotor C, or at a one-to-one ratio, power being transmitted through casing 85 and divided between the axle shafts l2 and 13 by the difcation may be "incorporated in the planetary ineohanismtto enable the shift-to be made Without declutching.

" From the foregoing disclosure it is apparent that; there is provided a drive axle embodying three speed reductions, one of which is constant, namely, the bevel gear reduction, and two-of which are variable, namely,-the spur geara'ss em bly andiplanetary'gear mechanism, andtha'tby operating levers-5i and lol four different speed ratios are available, by shifting them inva-rifous combinations. For instance, the spur gear reduction may be operatedin high or low gear,

and the planetary mechanism may be operated assembly is of novel form, permitting ready sub-, stitution, if. desired, of a modifiedcountershaft and closure. assembly to afford an additional planetary speed reduction between the bevel gear and countershaft.

Although Ih'ave shown the invention as embodied in a drive axle having a transversely split axle housing, it"is to be understood that if desired the housing may be of one-piece form, and

the counter and pinion shafts; together with the gear mechanisms, supported'in a bolted on auxiliary housing 'or carrier, without departing from the spirit of the invention.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in";

all respects as illustrative and not restrictive,

the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range 'of equivalency of the mounted for rotation about the axis of said axle 1 shafts; a two-speed spur gear assembly for transmitting power from said countershaft to said rotor; a two-speed planetary mechanism in said rotor for transmitting power from the latter to said axle shafts, said spur gear assembly be-- ing substantially Wholly disposed between a pair of parallel planes passing through the ends of said rotor and disposed normalto' said counter and axle shafts, said countershaft being mounted in spaced anti-friction bearings in said housing, at least one of said bearings beingwholly contained between said pair of spaced parallel planes passing through the ends of said rotor.

2. In a drive axle, a housing having a pairof axle shafts and a countershaft mounted for ro-v tation therein about substantially parallel axes;

gearmeans in said housing for transmitting power to said countershaft; a hollow rotor mounted for rotation about the axis of said axle ferential in; well known. manner-,1 It is'tobe 'iuid'erstoodthat the foregoingshi-fting operations are carried; out by momentarily releasing the vehicle clutch, but if desirecLI the easy shift. feature of the aforementioned. Brownyer lapplishafts; a two-speed spur gear assembly for transmitting power from said countershaft to said rotor; a two-speed planetary gear mechanism in said rotor for transmitting power from the latter to said axle shafts, comprising a casing rotatable in said housing about the axis ofsaid axle shafts between a pair of parallel planes passing through the ends of said rotor and disposed normal to said counter and axle shafts.

3. The drive axle defined in claim 2, wherein said means for transmitting power to said countershaft comprises a drive shaft rotatably mounted in said housing to one sideoiv said countershaft and disposed at right angles thereto, and

a bevel pinion on said drive shaft meshing with a bevel gear on said. countershaft, and said bevel gear and said planetary gear mechanism are located on opposite sides of a vertical plane containing the axis of said drive. shaft, with the bevel gear to one side of, but disposed in close prox- 15 imity to one end of, said rotor.

' LAWRENCE R; BUCKENDA Ee 

